1.) Complete part (c) of Exercise 1.5 in the textbook
-5, -5, 0, 0, 4, 6
2.) a.) Exercise 1.7
A - W
B - Z
C - V
D - Y
E - U
F - X
2.) b.) Describe the shape of each distribution A-F from a.) using correct terminology. A - Symmetric and unimodal
B - Skewed Right
C - SKewed Left
D - Distribution is spread out evenly from 0 to 10
E - Distribution is spread out to the extreme ends
F - Unimodal and not spread out and focused in the center
3.) Prove that the sum of deviations from the mean is equal to zero.
First we will expand the summation of the deviations. Then like terms will combine and cancel out :
\[
\sum_{n=1}^{\infty} (x_n - \bar{x} )= (x_1 - \bar{x} )+(x_2 - \bar{x} )+...+(x_n - \bar{x} ) \\
= (x_1 + x_2 +...+ x_n) - n(\bar{x})\\
=\sum_{n=1}^{\infty} (x_n) - \frac{n\sum_{n=1}^{\infty}(x_n)} n \\
\sum_{n=1}^{\infty}(x_n) - \sum_{n=1}^{\infty} (x_n) = 0
\] Since n times the mean is the same value of all the values added up, when subtracted the result is 0. Thus completing the proof.
4.)a.) Create a two way table of gender and participating in a sports team this fall.
library(fastR2)
## Loading required package: ggformula
## Loading required package: ggplot2
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## New to ggformula? Try the tutorials:
## learnr::run_tutorial("introduction", package = "ggformula")
## learnr::run_tutorial("refining", package = "ggformula")
## Loading required package: mosaic
## Loading required package: dplyr
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## Attaching package: 'dplyr'
## The following objects are masked from 'package:stats':
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## filter, lag
## The following objects are masked from 'package:base':
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## intersect, setdiff, setequal, union
## Loading required package: lattice
## Loading required package: mosaicData
## Loading required package: Matrix
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## The 'mosaic' package masks several functions from core packages in order to add
## additional features. The original behavior of these functions should not be affected by this.
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## Note: If you use the Matrix package, be sure to load it BEFORE loading mosaic.
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## Attaching package: 'mosaic'
## The following object is masked from 'package:Matrix':
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## mean
## The following objects are masked from 'package:dplyr':
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## count, do, tally
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## prop.test, quantile, sd, t.test, var
## The following objects are masked from 'package:base':
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## max, mean, min, prod, range, sample, sum
ClassSurvey = read.csv("C:/Users/jlwol/Downloads/ClassSurveyResults.csv", header=T, na.strings ="?")
head(ClassSurvey)
## Gender Class Greek Sports Prize Bed Pulse Work Height Number
## 1 Male Junior No Yes Olympic Medal 0:30 44 0 70 4
## 2 Male Junior No No Nobel Prize 0:00 54 5 71 6
## 3 Male Junior No No Nobel Prize 0:30 79 20 66 19
## 4 Male Senior No Yes Olympic Medal 23:30 80 2 65 4
## 5 Male Senior Yes Yes Nobel Prize 23:00 65 10 70 7
## 6 Female Junior Yes Yes Olympic Medal 1:30 66 12 64 18
table(ClassSurvey$Gender, ClassSurvey$Sports)
##
## No Yes
## Female 4 2
## Male 7 5
4.)b.) Create an appropriate graphical display to depict which award students in this class would prefer to win.
prizes = table(ClassSurvey$Prize)
barplot(prizes)
mosaicplot(prizes)
#Shows the Olympic Medal was the most prefered award.
4.)c.) Create an appropriate graphical display to depict the typical number of hours each student works per week
hist(ClassSurvey$Work, data = ClassSurvey)
## Warning in plot.window(xlim, ylim, "", ...): "data" is not a graphical
## parameter
## Warning in title(main = main, sub = sub, xlab = xlab, ylab = ylab, ...):
## "data" is not a graphical parameter
## Warning in axis(1, ...): "data" is not a graphical parameter
## Warning in axis(2, ...): "data" is not a graphical parameter
#The histogram shows that the majority of students work 0-5 hours or 15-20 hours.
4.)d.) Use appropriate graphical and numerical summaries to explore the relationship between a qualitative variable and a quantitative variable (of your choice) from the ‘ClassSurveyResults.csv’ file on Moodle. Write a few sentences to report findings.
histogram(~ClassSurvey$Height|ClassSurvey$Class)
#Shows two histograms one for the Juniors and one for the Seniors. The Juniors histogram showed a higher amount of taller students than the Senior students.
5.)
mean(ClassSurvey$Pulse)
## [1] 70.77778
sd(ClassSurvey$Pulse)
## [1] 13.08144
quantile(ClassSurvey$Pulse)
## 0% 25% 50% 75% 100%
## 44.00 64.25 71.00 79.00 98.00
boxplot(ClassSurvey$Pulse)